The problems haven't affected the California street line, so travelers from around the world can still hang off the runners as San Franciscans have for 135 years.

With the city and the SFMTA facing massive budget deficits, the problems are likely to raise serious questions about the costs and benefits of maintaining the service.

After all, it's hard to quantify exactly how big a draw Andrew Hallidie's 19th century contraption is for tourists, who neither have to put up with Muni service on a regular basis or vote in local elections.